/*
 * Copyright 2010-2012 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.jslet.paas.common;

import java.security.MessageDigest;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * <code>CipherUtils</code> is the utility class for dealing with cipher processing.
 * 
 * @author Tony Tong
 * @since jslet-paas 1.0
 */
public class CipherUtils
{
	private static final Logger logger = LoggerFactory.getLogger(CipherUtils.class);

	public static final String Digest(String credentials, String algorithm, String encoding)
	{
		try
		{
			MessageDigest md = (MessageDigest) MessageDigest.getInstance(algorithm).clone();

			if (encoding == null)
				md.update(credentials.getBytes());
			else
			{
				md.update(credentials.getBytes(encoding));
			}

			return HexUtils.byte2hex(md.digest());
		}
		catch (Exception ex)
		{
			logger.error(ex.getMessage());
		}
		return credentials;
	}
}
